The Western Stone Forts Project: Excavations at Dún Aonghasa and Dún Eoghanachta, volumes 1 and 2, by Claire Cotter

An ambitious project studying the great stone forts of western Ireland is yielding rich results

Thu, Oct 17, 2013, 12:18


Book Title:
The Western Stone Forts Project: Excavations at Dún Aonghasa and Dún Eoghanachta, volumes 1 and 2


Claire Cotter


Guideline Price:

On the 1990s, the Discovery Programme initiated an ambitious project to study the great stone forts of western Ireland. The first two volumes of the report on that research, largely written by Claire Cotter, have now appeared. The Western Stone Forts Project involved not alone a survey of a large number of monuments but also the excavation of two major sites on Árainn (or Inis Mór, as the author reluctantly calls it). One of the sites excavated is the famous and spectacular Dún Aengus, built on the edge of a sea cliff. The fort has been a symbol of Ireland ever since references to it began to appear in the 19th-century scientific and tourism literature. The other is Dún Eoghanachta, which appears to have been built in the early medieval period and which produced material typical of that time.

The Aran Islands have seven very substantial stone forts; island cultures for some reason frequently express themselves in spectacular structures. (Consider the sculptures of Easter Island or the Neolithic temples and present-day huge parish churches of Malta.) The rugged grandeur of the Aran forts is so striking that it has inspired a plethora of popular ideas that have little connection to the facts as we know them. Now, thanks to these two volumes, we are much better informed. They are the first in a series and are divided only as a matter of convenience – they are paginated as a single publication. The third volume will be a virtual one (soon to be available at, and volumes 4 and 5 are expected in about a year. They will deal with the wider geographical and archaeological context of the forts, which have interesting analogues along the Atlantic seaboard from Iberia to the Hebrides. Whether these are all linked in some direct manner or whether their resemblances are the predictable outcome of using common techniques of building drystone defensive structures will no doubt be discussed.

Dún Aengus is a hill fort enclosed by three stone walls. Its history is complex and understood now through the hard-won evidence of survey and excavation. Cotter writes very well and imparts enough background to enable us to see the fort in its prehistoric and historic contexts. She is aided by a battery of specialists, some of whose reports are printed while others are to appear in electronic form. There are 35 named collaborators, some of them writing accessibly about demanding subjects, others expressing themselves in specialist jargon but making up in precision what they lack in literary style.

In the first chapter, Cotter discusses the character of the western forts included in the study and briefly traces the development of the idea that all these monuments, from Grianan Aileach, in Co Donegal, to Staigue fort, in Co Kerry, might be aspects of a common phenomenon. Scholarly opinion first developed in the 19th century at a time when it was considered reasonable to use legends to provide insight into the history of the forts (to some they were the work of the Fir Bolg) until TJ Westropp, at end of the century, established the scientific basis for the study of Irish defensive structures.

The second chapter deals with the character of the islands, with sections on geology and soils, flora and fauna. These are followed by a comprehensive survey of their archaeology: human settlement began, it seems, at the end of the Neolithic period or during the earlier Bronze Age; evidence for even earlier activity is lacking, although some wag planted a Palaeolithic artefact in the chevaux de frise of Dún Aengus.

In addition to the seven great stone forts, there are on the islands early-medieval sites such as ring forts and ecclesiastical foundations of importance. The account brings the story up to early modern times. Anyone writing about Árainn could well be intimidated by the evocative writings of Tim Robinson, but these more matter-of-fact descriptions have a different, austere, scientific purpose, and they are all the better for that.

The third chapter traces the construction and modification of the successive phases of the stone walls of Dún Aengus; one of these is a short stretch of wall unconnected to any other feature ,and three of them define the substantial enclosures known so well from aerial photographs.

This is a very complex and detailed account. The famous chevaux de frise , a densely placed series of monoliths designed to frustrate attackers much as the barbed-wire entanglements of modern warfare did, is an important element of the defences. Its date is far from certain. The structural history can be difficult to follow. It may be best to skip to chapter 13 in volume two.

Despite the severe conditions of wind erosion, a surprising number of objects and evidence for dwellings and burial were recovered and enabled the excavator to propose the sequence of occupation and construction of the site supported by radiocarbon dating which is explained in full in volume two.

There are slight traces of human activity on the site in the period c1500 to 1000 BC but no firm evidence of settlement. Around 1000 BC, during the late Bronze Age, the hill fort was constructed, on a plan that persists to this day. At least two of the three enclosing walls were probably built about this time, the innermost and the middle wall. Dún Aengus produced valuable evidence of settlement structures, subsistence and the manufacture of bronze objects.

Later modifications to the fortifications took place, some of them just a couple of centuries after the initial building of the hill fort. More was built during the Iron Age (c700 BC to AD c400) and later, when the fort was remodelled again, between 500 and 1000 AD. The innermost wall was raised to a considerable height, which gave it the appearance of a citadel within the other ancient ramparts. Its walls were thickened and terraces were built.

This bald summary does not do justice to the richness of Cotter’s account or to the work of her collaborators. The promised volumes will take the study in new directions, but for the present we have this valuable and complex text – just what the expert will appreciate.

It would be a great service to our heritage if Claire Cotter were to produce in her admirably clear style a short, popular book to bring the results of her research to the widest possible audience.

Michael Ryan is an archaeologist and was chairman of the Discovery Programme 2001-2011.